text: Silyl groups can be deprotected with fluoride ions resulting in a strong Si-F bond that is hard and challenging to break. For this reason, different polymer chemists started to employ PPA in fluoride sensing by using t-butyldimethylsily<nowiki/>l (TBS) containing initiators and terminators. The fluoride sensing ability of PPA has been previously used in applications such as drug release, as previously reported by DiLauro et al. Another application studied by Phillips and co-workers includes the use of fluoride-triggered PPA depolymerization in changing the structure of plastics in a predetermined way.